Our main objective is immunotherapy of mouse leukemias by use of potent, specific antisera, coupled with chemotherapy and immune stimulation. These model system studies are intended to be of use in the clinical treatment of leukemia. In addition, work is in progress on antigens present in bronchogenic carcinoma as a possible approach to the early diagnosis of lung cancer. Our approach to the first problem is to attempt rabbit antisera production to produce sera of relatively high specificity and low toxicity. Because these antisera have been insufficient to perform cures in meaningful mouse test systems, we have used chemotherapy with cytoxan and BCNU to reduce the tumor cell mass, in addition to treatment with rabbit antisera of "directed" specificity. We are exploring the addition of antigenic stimulation by use of vaccines prepared by chemically altering the tumor cells. For this purpose we are presently testing a new method for increasing the antigenicity of tumor cells. With regard to the immune response of the mice bearing the tumors and the effect of treatment schedules on this response, we are planning to perform in vitro assays of cell-mediated immunity at various time-points during the therapy regimen. In the work bronchogenic carcinoma antigens, we have completed a study using frozen sections of tumor to look for specific staining with the fluorescent antibody technique. We plan to extend this work to the use of cultured cell lines instead of frozen tissue sections. BIBLIOGRAPHIC REFERENCES: Reif, A.E., and Robinson, C.M. Immune cytolysis by automatic determination of cell volume distribution. Federation Proc. 35:671 (1976). Rief, A.E., and Robinson, C.M.: Enzymatic degradation of tumor cells damaged by antibody plus complement. J. Immunology, Aug., (1976), in press.